Field of the Invention
The present disclosure relates to a developing member incorporated into electrophotographic apparatuses such as copiers, printers and facsimile receivers, the developing member being brought into contact with or close to an image bearing member in use. The present disclosure also relates to a process cartridge and an electrophotographic image forming apparatus.
Description of the Related Art
In electrophotographic apparatuses such as copiers, fax machines and printers, an image bearing member is charged by a charging unit, and an electrostatic latent image is formed by a laser. Next, a toner in the developing container is applied onto a developing member by a toner feed roller and a toner regulating member to develop the electrostatic latent image with the toner by bringing the image bearing member into contact with or close to the developing member. Subsequently, the toner on the image bearing member is transferred onto a recording paper by a transferring unit, and the toner on the recording paper is fixed under heat and pressure. The residual toner on the image bearing member is removed by a cleaning blade.
Image forming apparatuses of a non-magnetic one-component contact developing system typically include an electro-conductive electrophotographic member having a volume resistivity of 103 to 1010 Ωcm as the developing member. Higher performance has been required for the developing member for electrophotographic image forming apparatuses, and two-layer developing members including an electro-conductive elastic layer and an electro-conductive surface layer disposed on the surface of the electro-conductive elastic layer have been increasingly used from the viewpoint of high image quality and high durability. The electro-conductive surface layer broadly used is composed of a urethane resin having high resistance to wear and toner charging properties. Recently, to attain higher function, Japanese Patent Application Laid-Open No. 2015-094897 discloses that enhanced toner charging properties can be provided by containing alumina in a surface layer and thus high-quality images can be provided.